[j-nsp] EX4200 console port woes

[Chuck Anderson]

On Thu, Dec 31, 2015 at 12:30:51PM -0500, Eric Van Tol wrote:
> > The default console speed on the EX4200 is 9600bauds, as stated here :
> > 
> > http://www.juniper.net/techpubs/en_US/release-independent/junos/information-
> > products/topic-collections/hardware/ex-series/ex3200-4200/topic-42349.html
> > 
> > Eric's settings looks fine, unless he missed a change in console speed
> > configuration.
> 
> Correct, but I did try different speeds just as a test, with no change. It *does* mimic a speed issue, though. 
> 
> Tried other ports, other EX switches, other cables.
> 
> There seems to be something specific with the EX console port that this MRV does not like. Again, the problem does not appear to be the console port itself, as it works perfectly when I access it by other means. And again, I can simply move the cable into any other device that isn't an EX switch and I get proper communication on that port.

What is the exact pinout of the MRV <---> EX connection you are using?
Perhaps there is something strange with the handshake lines that is
only affecting EX-on-MRV?  For example, is CD tied locally to DSR as
well as DTR on the far end?  I never do this with my EX <--->
Cyclades/Avocent connections and it works fine, but if your cable
arrangement is doing this perhaps it is causing a problem, or if the
MRV is expecting this and you aren't doing it perhaps that is the
problem...

https://en.wikipedia.org/wiki/Null_modem